Bats are depicted in some cultures as devil-like vampires through images of death and Halloween. But in others they are the opposite and are believed to bring luck and good fortune in China. Fear of bats has been exacerbated in the past 18 months by the Coronavirus pandemic and a blame game, pointing the finger at bats as a potential source of Covid-19. But environmentalists love them for being natural pest controllers – hoovering up harmful insects. Scientists love them too - as a vital source of medical research. How can they carry viruses without getting ill and what is their anti-ageing secret?